Topiramate precipitating a manic episode in a bipolar patient comorbid with binge eating disorder: A case report

RATIONALE

Topiramate is a novel antiepileptic drug that is used as an adjunctive in the treatment of partial and secondary generalized seizures. In recent years, psychiatrists have paid more attention to topiramate as a mood stabilizer and as an agent for treating eating disorders, especially in binge eating disorder (BED) and bulimia nervosa.

PATIENT CONCERNS AND DIAGNOSES

Herein, we report a case of topiramate precipitating a manic episode in a bipolar patient comorbid with BED, who complained of emotional instability and binge-eating behaviors.

DIAGNOSES

In this patient, acute manic episode was induced by topiramate treatment at a daily dose of 75 mg for three days.

INTERVENTIONS

The dose of topiramate was decreased to 25 mg per day promptly, and the patient gradually became calm but the BED symptoms recurred, then the dose of topiramate was increased to 50 mg per day again. Meanwhile, the dosage of quetiapine was escalated up to 500 mg per night to stabilize her mood.

OUTCOMES

With a combination of quetiapine 500 mg per night and topiramate 50 mg per day, the emotion and eating problems of this patient concurrently improved.

LESSONS

These findings indicated that patients with a history of bipolar disorder and comorbid BED have a tendency to develop manic episode when taking topiramate. Careful monitoring of mood alterations after topiramate supplement to mood stabilizers is necessary in this population.

A proposal for standardized magnetic resonance imaging (MRI) descriptors of abnormally invasive placenta (AIP) - From the International Society for AIP

Abnormally invasive placenta (AIP) is used to describe a placenta that does not separate naturally after delivery and cannot be extirpated without causing abnormally high blood loss. Recently, the use of a standardized terminology for descriptors of AIP signs seen on ultrasound has been prosed but to date no such unified descriptors have been developed for magnetic resonance imaging (MRI). The purpose of this paper is to propose a unified terminology based on a consensus opinion from the members of the International Society for AIP (IS-AIP) that include obstetricians, gynecologists, radiologists, pathologists, anesthesiologists and basic science researchers. We assume that using these standardized MRI descriptors for AIP will be useful for clinical use, education, teaching and future research projects, thus assumably improving care of patients with this condition. In addition, using a uniform terminology for AIP should become the first step of a standardized MRI report.

Immunogenicity and safety of an accelerated hepatitis E vaccination schedule in healthy adults: a randomized, controlled, open-label, phase IV trial

OBJECTIVES

This study aimed to evaluate the immunogenicity and safety of a hepatitis E (HE) vaccine using an accelerated vaccination schedule (vaccine doses at 0, 7 and 21 days).

METHODS

A total of 126 participants aged ≥18 years were randomly assigned to receive the hepatitis E virus vaccine in either the accelerated group (0, 7 and 21 days) or the routine group (0, 1 and 6 months). Serology samples were obtained at 0, 21, 28 and 51 days, and 7 months in the accelerated group, or 0, 1, 2 and 7 months in the routine group after the first vaccine injection. Adverse events (AEs) reported during the whole study were analysed.

RESULTS

A total of 126 participants were randomized, 63 for each group. Sixty-two participants in the accelerated group and 63 in the routine group received at least one dose of vaccine; 57 and 63 participants received all three doses and were included in per-protocol set, respectively. In the per-protocol population, at 1 month after the last dose (accelerated group at 51 days versus routine group at 7 months), the seropositive rates were both 100% (57/57 and 63/63, respectively), and the geometric mean concentrations (GMCs) were 8.51 WHO units/mL (95% CI 6.73-10.76) in the accelerated group and 9.67 WHO units/mL (95% CI 7.67-12.20) in the routine group. The ratio of the accelerated group GMC to the routine group GMC was 0.88 (95% CI 0.61-2.17, lower limit of 95% CI > 0.5), indicating that the accelerated vaccination schedule was non-inferior to the routine one. The overall incidence rates of solicited AEs in the accelerated and routine groups were 32.26% (20/62) and 30.16% (19/63), respectively (p 0.800). Most AEs were moderate.

CONCLUSIONS

An accelerated schedule is safe and provides protective antibodies in a shorter time compared with the routine schedule. The accelerated schedule should be recommended to adults who are travelling on short notice to an HE-endemic area or during an HE outbreak (Clinical Trial Registration. NCT03168412).

Strategies to improve the efficiency of mesenchymal stem cell transplantation for reversal of liver fibrosis

End‐stage liver fibrosis frequently progresses to portal vein thrombosis, formation of oesophageal varices, hepatic encephalopathy, ascites, hepatocellular carcinoma and liver failure. Mesenchymal stem cells (MSCs), when transplanted in vivo, migrate into fibrogenic livers and then differentiate into hepatocyte‐like cells or fuse with hepatocytes to protect liver function. Moreover, they can produce various growth factors and cytokines with anti‐inflammatory effects to reverse the fibrotic state of the liver. In addition, only a small number of MSCs migrate to the injured tissue after cell transplantation; consequently, multiple studies have investigated effective strategies to improve the survival rate and activity of MSCs for the treatment of liver fibrosis. In this review, we intend to arrange and analyse the current evidence related to MSC transplantation in liver fibrosis, to summarize the detailed mechanisms of MSC transplantation for the reversal of liver fibrosis and to discuss new strategies for this treatment. Finally, and most importantly, we will identify the current problems with MSC‐based therapies to repair liver fibrosis that must be addressed in order to develop safer and more effective routes for MSC transplantation. In this way, it will soon be possible to significantly improve the therapeutic effects of MSC transplantation for liver regeneration, as well as enhance the quality of life and prolong the survival time of patients with liver fibrosis.

The Impacts of Childhood Trauma on Psychosocial Features in a Chinese Sample of Young Adults

OBJECTIVE

The aims of the present study were to explore the occurrence of childhood trauma and importantly to determine the impacts of childhood trauma on psychosocial features in a Chinese sample of young adults.

METHODS

A survey was carried out in a group of 555 university students by using Childhood Trauma Questionnaire (CTQ), Self-rating Depression Scale (SDS), Self-rating Anxiety Scale (SAS), Dysfunctional Attitudes Questionnaire (DAS), Eysenck Personality Questionnaire (EPQ), and Social Support Rating Scale (SSRS). The moderate-severe cut-off scores for CTQ were used to calculate the prevalence of childhood trauma, and then psychosocial features were compared between individuals with and without childhood trauma.

RESULTS

A proportion of 18.6% of university students had self-reported childhood trauma exposures. Subjects with childhood trauma reported higher scores of SDS, SAS, DAS, and psychoticism and neuroticism dimensions of EPQ (t=4.311-5.551, p<0.001); while lower scores of SSRS and extraversion dimension of EPQ (t=-4.061- -3.039, p<0.01). Regression analyses further revealed that scores of SAS and DAS were positively (Adjusted B=0.211-0.230, p<0.05), while scores of SSRS were negatively (Adjusted B=-0.273- -0.240, p<0.05) associated with specific CTQ scores.

CONCLUSION

Childhood trauma is still a common social and psychological problem. Individuals with childhood trauma show much more depression, anxiety, distorted cognition, personality deficits, and lower levels of social support, which may represent the social and psychological vulnerability for developing psychiatric disorders after childhood trauma experiences.

[Technical specification for clinical application of critical ultrasonography]

Critical ultrasonography(CUS) is different from the traditional diagnostic ultrasound, the examiner and interpreter of the image are critical care medicine physicians. The core content of CUS is to evaluate the pathophysiological changes of organs and systems and etiology changes. With the idea of critical care medicine as the soul, it can integrate the above information and clinical information, bedside real-time diagnosis and titration treatment, and evaluate the therapeutic effect so as to improve the outcome. CUS is a traditional technique which is applied as a new application method. The consensus of experts on critical ultrasonography in China released in 2016 put forward consensus suggestions on the concept, implementation and application of CUS. It should be further emphasized that the accurate and objective assessment and implementation of CUS requires the standardization of ultrasound image acquisition and the need to establish a CUS procedure. At the same time, the standardized training for CUS accepted by critical care medicine physicians requires the application of technical specifications, and the establishment of technical specifications is the basis for the quality control and continuous improvement of CUS. Chinese Critical Ultrasound Study Group and Critical Hemodynamic Therapy Collabration Group, based on the rich experience of clinical practice in critical care and research, combined with the essence of CUS, to learn the traditional ultrasonic essence, established the clinical application technical specifications of CUS, including in five parts: basic view and relevant indicators to obtain in CUS; basic norms for viscera organ assessment and special assessment; standardized processes and systematic inspection programs; examples of CUS applications; CUS training and the application of qualification certification. The establishment of applied technology standard is helpful for standardized training and clinical correct implementation. It is helpful for clinical evaluation and correct guidance treatment, and is also helpful for quality control and continuous improvement of CUS application.

Characterization and transplantation of enteric neural crest cells from human induced pluripotent stem cells

The enteric nervous system (ENS) is recognized as a second brain because of its complexity and its largely autonomic control of bowel function. Recent progress in studying the interactions between the ENS and the central nervous system (CNS) has implicated alterations of the gut/brain axis as a possible mechanism in the pathophysiology of autism spectrum disorders (ASDs), Parkinson's disease (PD) and other human CNS disorders, whereas the underlying mechanisms are largely unknown because of the lack of good model systems. Human induced pluripotent stem cells (hiPSCs) have the ability to proliferate indefinitely and differentiate into cells of all three germ layers, thus making iPSCs an ideal source of cells for disease modelling and cell therapy. Here, hiPSCs were induced to differentiate into neural crest stem cells (NCSCs) efficiently. When co-cultured with smooth muscle layers of ganglionic gut tissue, the NCSCs differentiated into different subtypes of mature enteric-like neurons expressing nitric oxide synthase (nNOS), vasoactive intestinal polypeptide (VIP), choline acetyltransferase (ChAT) or calretinin with typical electrophysiological characteristics of functional neurons. Furthermore, when they were transplanted into aneural or aganglionic chick, mouse or human gut tissues in ovo, in vitro or in vivo, hiPSC-derived NCSCs showed extensive migration and neural differentiation capacity, generating neurons and glial cells that expressed phenotypic markers characteristic of the enteric nervous system. Our results indicate that enteric NCSCs derived from hiPSCs supply a powerful tool for studying the pathogenesis of gastrointestinal disorders and brain/gut dysfunction and represent a potentially ideal cell source for enteric neural transplantation treatments.

109 Dosage Compensation of the X Chromosome in Ovine Embryos, Late Gestation, and Adult Somatic Tissues

Deviations from proper gene dosage of the autosome range from severe to lethal consequences in mammals. Eutherian males (XY), however, have reduced gene dosage compared with females (XX) due to a single X and deteriorating Y chromosome. This dosage imbalance is resolved through X chromosome dosage compensation, according to Ohno’s hypothesis: X-linked gene expression is doubled in both males and females to balance expression of the X chromosome and autosomes. To compensate for doubled X chromosome expression in females, X chromosome inactivation (XCI) inactivates a single X chromosome in each cell. Although these mechanisms have been well studied in mice and humans, controversies exist due to the analysis and interpretation of RNA sequencing data. Here we described X chromosome dosage compensation in the sheep. Twelve ewes were fed 100% (control), 60% (restricted), or 140% (overfed) of the National Research Council requirements for a ewe pregnant with twins (NRC, 1985; Nutrient Requirements of Sheep, 6th ed.). Day 135 brain, lung, and kidney tissues were collected from fetuses of the control, restricted, and overfed groups (n = 7, 4, and 4; respectively). RNA seq libraries were prepared using the Illumina TruSeq stranded mRNA kit and sequenced on the NextSEqn 500 (Illumina Inc., San Diego, CA, USA). Two additional RNA-seq datasets were downloaded from Sequence Read Archive (SRA), including Day 14 embryos (PRJNA254105), and adult and juvenile heart, brain, liver, muscle, rumen, and female- and male-specific tissues (PRJEB6169). The RNA-seq data were trimmed and mapped to the ovine reference genome assembly Oar_v4.0 using Hisat2 (version 2.0.5; https://ccb.jhu.edu/software/hisat2/index.shtml) aligner. The mRNA level of each gene was estimated by transformed transcripts per kilobase million (TPM) and was quantified using IsoEM (version 1.1.4; http://dna.engr.uconn.edu/). The relative expression of X to autosomal (A)(RXE) was calculated using RXE = log2(X expression) – log2(A expression) with an average of 486 X-linked genes and 13,001 autosomal genes after TPM >1 filtering. RXE ≥0 (or X:A ratio ≥ 1); <0, = –1 indicate complete, incomplete, or no dosage compensation; respectively. Control, restricted, and overfed ovine fetal somatic tissues displayed incomplete dosage compensation. Incomplete dosage compensation was also observed in juvenile and adult somatic major organs and female specific tissues. Brain tissues, apart from the cerebellum, displayed complete dosage compensation with an RXE range of 0 to 0.16. An interesting pattern was observed in the male specific tissues with complete dosage compensation in the epididymis (RXE = 0.32) and incomplete dosage compensation in the testes (RXE = –0.84). No significant RXE differences were observed between ovine female and male somatic tissues, supporting Ohno’s hypothesis of balanced expression of X-linked genes to autosomal genes. Our results indicate that a mechanism for dosage compensation exists in the sheep, although it is largely incomplete.

Memantine induces manic episode in a 73-year-old patient with vascular neurocognitive disorder: a case report

Memantine, an N-methyl-d-aspartate receptor antagonist, is a well-established treatment option for moderate-to-severe cognitive impairment related to Alzheimer disease. Recently, growing evidence has indicated memantine might also be effective in treatment of affective disorders. The common drug-induced adverse events of memantine include confusion, dizziness, drowsiness, headache, insomnia, and agitation. Herein, we presented a case of a 73-year-old female patient with vascular neurocognitive disorder, who developed a manic episode after taking memantine.

Intracranial hypertension induced by internal jugular vein stenosis can be resolved by stenting

BACKGROUND AND PURPOSE

Idiopathic intracranial hypertension (IIH) is characterized by abnormally elevated intracranial pressure (ICP) without identifiable etiology. Recently, however, a subset of patients with presumed IIH have been found with isolated internal jugular vein (IJV) stenosis in the absence of intracranial abnormalities.

METHODS

Fifteen consecutive patients were screened from 46 patients suspected as IIH and were finally confirmed as isolated IJV stenosis. The stenotic IJV was corrected with stenting when the trans-stenotic mean pressure gradient (∆MPG) was equal to or higher than 5.44 cmH₂ O. Dynamic magnetic resonance venography, computed tomographic venography and digital subtraction angiography of the IJV, ∆MPG, ICP, Headache Impact Test 6 and the Frisén papilledema grade score before and after stenting were compared.

RESULTS

All the stenotic IJVs were corrected by stenting. ∆MPG decreased and the abnormal collateral veins disappeared or shrank immediately. Headache, tinnitus, papilledema and ICP were significantly ameliorated at 14 ± 3 days of follow-up (all P < 0.01). At 12 ± 5.6 months of outpatient follow-up, headache disappeared in 14 out of 15 patients (93.3%), visual impairments were recovered in 10 of 12 patients (83.3%) and tinnitus resolved in 10 out of 11 patients (90.9%). In 12 out of 15 cases, the Frisén papilledema grade scores declined to 1 (0-2). The stented IJVs in all 15 patients kept to sufficient blood flows on computed tomographic venography follow-up without stenting-related adverse events.

CONCLUSIONS

Non-thrombotic IJV stenosis may be a potential etiology of IIH. Stenting seems to be a promising option to address the issue of intracranial hypertension from the etiological level, particularly after medical treatment failure.

Association between procalcitonin levels and carotid atherosclerosis in acute ischemic stroke patients

BACKGROUND AND PURPOSES

Procalcitonin has been suggested as a new risk factor in atherosclerotic disease. However, whether procalcitonin levels are associated with the risk of carotid atherosclerosis remains unclear. This study aimed to investigate the relationship between procalcitonin levels and carotid atherosclerosis among patients with first-ever acute ischemic stroke.

METHODS

Two hundred and thirty consecutive patients were prospectively enrolled in this study. Serum procalcitonin concentrations were measured at admission for all patients. We also performed ultrasound examination to detect the mean carotid intima-media thickness, presence of carotid-wall thickening, plaque and significant stenosis. Multiple regression analysis was used to estimate the association between procalcitonin levels and carotid atherosclerosis.

RESULTS

The median procalcitonin concentration was 0.051 µg/L (interquartile range, 0.036-0.080 µg/L). Of the 230 patients, 102 (44.3%) had carotid-wall thickening, 113 (49.1%) had plaque and 77 (33.5%) had significant stenosis. After adjusting for all potential confounders by multiple logistic regression analysis, patients with procalcitonin levels in the fourth quartile, compared with the first quartile, were more likely to have carotid-wall thickening [odds ratio 2.288, 95% confidence intervals 1.042-5.021, P = 0.039] and significant stenosis [odds ratio 3.871, 95% confidence intervals 1.690-8.867, P = 0.003]. Furthermore, the linear regression analysis revealed a significant positive correlation between procalcitonin levels and the mean carotid intima-media thickness (β = 0.162, P = 0.012).

CONCLUSIONS

Higher procalcitonin concentrations at admission might be associated with carotid-wall thickening and significant stenosis in ischemic stroke patients.

Mechanistic Oral Absorption Modeling and Simulation for Formulation Development and Bioequivalence Evaluation: Report of an FDA Public Workshop

On May 19, 2016, the US Food and Drug Administration (FDA) hosted a public workshop, entitled “Mechanistic Oral Absorption Modeling and Simulation for Formulation Development and Bioequivalence Evaluation.”1 The topic of mechanistic oral absorption modeling, which is one of the major applications of physiologically based pharmacokinetic (PBPK) modeling and simulation, focuses on predicting oral absorption by mechanistically integrating gastrointestinal transit, dissolution, and permeation processes, incorporating systems, active pharmaceutical ingredient (API), and the drug product information, into a systemic mathematical whole‐body framework.2

Prognostic significance of the T2 substage in patients with esophageal squamous cell carcinoma

The invasion of the muscularis propria is defined as T2 stage in esophageal squamous cell carcinoma. Evidence is lacking regarding whether the T2 substage based on anatomy may serve as a prognostic indicator. This study aims to confirm the prognostic value of the T2 substage. The clinicopathological characteristics of 120 patients who had pathologically verified T2 tumors between 2006 and 2011 at the Tianjin Medical University Cancer Institute and Hospital were retrospectively studied. Based on the invasion depth, tumors that had penetrated the circular muscle layer were defined as T2a, while T2b disease referred to those that had invaded the longitudinal muscle layer. Factors potentially related to survival were analyzed with univariate and multivariate analyses. The logistic regression model was used to examine the factors associated with lymph node metastasis. To verify the prognostic value of the T2 substage further, patients with T1b and T3 stage disease during the same period were selected for comparisons. The univariate and multivariate analyses demonstrated that the T2 substage and N stage were independent prognostic factors. The T2 substage was highly relevant to lymph node metastasis in the logistic regression model (P = 0.044). When T1b and T3 was considered, the survival of T2a patients was closer to that of T1b patients, while the survival of T2b patients was closer to that of T3 disease (P = 0.000). The T2 substage was an independent prognostic factor. Patients with T2a tumors displayed a favorable survival, while the prognosis of T2b patients was closer to that of T3 patients.

Transcriptome sequencing study implicates immune-related genes differentially expressed in schizophrenia: new data and a meta-analysis

We undertook an RNA sequencing (RNAseq)-based transcriptomic profiling study on lymphoblastoid cell lines of a European ancestry sample of 529 schizophrenia cases and 660 controls, and found 1058 genes to be differentially expressed by affection status. These differentially expressed genes were enriched for involvement in immunity, especially the 697 genes with higher expression in cases. Comparing the current RNAseq transcriptomic profiling to our previous findings in an array-based study of 268 schizophrenia cases and 446 controls showed a highly significant positive correlation over all genes. Fifteen (18%) of the 84 genes with significant (false discovery rate<0.05) expression differences between cases and controls in the previous study and analyzed here again were differentially expressed by affection status here at a genome-wide significance level (Bonferroni P<0.05 adjusted for 8141 analyzed genes in total, or P<~6.1 × 10^-6), all with the same direction of effect, thus providing corroborative evidence despite each sample of fully independent subjects being studied by different technological approaches. Meta-analysis of the RNAseq and array data sets (797 cases and 1106 controls) showed 169 additional genes (besides those found in the primary RNAseq-based analysis) to be differentially expressed, and provided further evidence of immune gene enrichment. In addition to strengthening our previous array-based gene expression differences in schizophrenia cases versus controls and providing transcriptomic support for some genes implicated by other approaches for schizophrenia, our study detected new genes differentially expressed in schizophrenia. We highlight RNAseq-based differential expression of various genes involved in neurodevelopment and/or neuronal function, and discuss caveats of the approach.

Identification of Magnolia wufengensis (Magnoliaceae) cultivars using phenotypic traits, SSR and SRAP markers: insights into breeding and conservation

A combination of phenotypic characterization and molecular markers may provide reliable information on new plant varieties and elucidate the conservation status of rare species. Five newly developed Magnolia wufengensis cultivars, an endangered plant species endemic to Hubei Province, China, possess more distinctive phenotypes than common Magnolia cultivars. With reference to a wild species population of M. wufengensis and a population of Magnolia denudata, morphological traits of flower organs, simple sequence repeat (SSR), and sequence-related amplified polymorphism (SRAP) markers were used. In the morphological study, six traits of floral organs were investigated and their relationships were analyzed between cultivars. In the genetic study, 9 SSR primer pairs and 10 SRAP primer combinations were screened. The five cultivars maintained a high level of genetic diversity. Genetic diversity of each M. wufengensis cultivar was much lower than that of the wild population, but was slightly higher than that of the M. denudata population. Analysis of molecular variance (AMOVA) revealed that genetic variation among populations was 20% (SRAP) and 30% (SSR), which showed a high degree of genetic differentiation among populations of the five cultivars. The dendrograms illustrated a clear separation between M. wufengensis populations and outer species, and identified two major groups among cultivars. Correlation analysis indicated a good fit between the two marker systems, but a relatively low fit between morphological and genetic traits (SRAP: r = 0.60, SSR: r = 0.52). These findings provide reliable references for the application of these molecular markers in the breeding and conservation of M. wufengensis.

125 INCOMPLETE COMPENSATORY UP-REGULATION OF X-LINKED GENES IN BOVINE GERMLINE, EARLY EMBRYOS, AND SOMATIC TISSUES

The maintenance of a proper gene dosage is essential in cellular networks. To resolve the dosage imbalance between eutherian females (XX) and male (XY), X chromosome inactivation (XCI) occurs in females, while X-chromosome dosage compensation up-regulates the active X to balance its expression with that of autosome pairs [Ohno’s hypothesis; Ohno 1967 Sex Chromosomes and Sex-linked Genes (Springer-Verlag), p. 99]. These phenomena have been well studied in humans and mice, despite many controversies over the existence of such up-regulation. Using RNA sequencing data, we determined X chromosome dosage compensation in the bovine by analysing the global expression profiles of germ cells, embryos, and somatic tissues. Eight bovine RNA-seq data sets were obtained in from the Gene Expression Omnibus, covering bovine immature/mature oocytes (GSE59186 and GSE52415), pre-implantation conceptuses (GSE59186, GSE52415, and GSE56513), extra-embryonic tissues (PRJNA229443), and male/female somatic tissues (GSE74076, GSE63509, PRJEB6377, and GSE65125). The RNAseq data were trimmed and non-uniquely (paralogs included) mapped to the bovine reference genome assembly UMD3.1.1 using Hisat2 (version 2.0.5) aligner. The mRNA level of each gene, estimated by transformed transcripts per kilobase million was quantified by IsoEM (version 1.1.5). These RNA-seq data sets represented 4 chromosome scenarios in cells: XXXX:AAAA (diploid immature oocyte with DNA duplication), XX:AA (haploid mature oocyte with DNA duplication), XX:AA and X:AA (gradual changed X status in bovine pre-implantation conceptuses), and X:AA (extra-embryonic tissues and somatic cells in female with one active X or XY male) were analysed for dosage compensation. A total of 959 X-linked genes and 20,316 autosome genes were used to calculate the relative X to autosomal gene (A) expression (RXE): log2 (X expression) − log2 (A expression). The following dosage determinations were made: RXE values ≥ 0: complete dosage compensation (or X: A ratio ≥ 1); RXE values < 0: in-complete dosage compensation; RXE value = −1: no dosage compensation (or X: A ratio = 0.5). Our analyses showed a decreased RXE after fertilization, from −0.33 in matured oocytes to −0.50 at the 2-cell stage, indicating that the sperm that undergo meiotic sex chromosome inactivation (MSCI) bring in inactive X chromosomes to the matured oocytes. Subsequently, the activation of the bovine embryonic genome at the 4- to 8-cell stage increased RXE from −0.54 to −0.05. This was followed by a sharp RXE decline from −0.02 at the 16-cell stage, 0.1 at the 32-cell stage to −0.29 at the compact morula stage, which is known as paternal X inactivation stage in the bovine. Finally, RXE was stabilised from blastocysts −0.19 through the Day 19 conceptuses −0.25 to somatic tissue average −0.21 with a pattern of incomplete X compensation. These findings support X expression up-regulation as proposed by Ohno. No significant RXE differences were observed between bovine female and male somatic tissues, further supporting Ohno’s hypothesis, which predicts a balance in the expression of X-linked genes to that of autosomes. This study confirms Ohno’s hypothesis of X dosage compensation in bovine germ cells, early embryos, and somatic tissues.

127 ABUNDANCE OF mRNA FOR HISTONE VARIANTS, HISTONE, AND DNA MODIFICATION ENZYMES IN BOVINE IN VIVO OOCYTES AND PRE-IMPLANTATION EMBRYOS

During early embryogenesis, chromatin composition and structure undergo dramatic changes due to replacement of canonical histones by histone variants, post-translational modifications of histones, and changes in DNA methylation. These dynamics of chromatin play important roles in the regulation of gene expression and development of embryonic cells. Our goal here is to describe the above-mentioned changes using recently established transcriptome profiles of bovine in vivo-produced oocytes and pre-implantation embryos (Jiang et al. 2014 BMC Genomics, 15, 1). Ten multiparous Holstein cows were synchronized and superovulated. Artificial insemination was conducted at 12 and 24 h post-standing heat using semen from bulls of proven fertility. In vivo-matured oocytes and 2- to 16-cell stage embryos were collected at 30 h, and 2 to 4 days after oestrus by oviducal flushing. Early morulae, compact morulae, and blastocysts were collected by non-surgical uterine flushing on days 5, 6, and 7 after oestrus. Single-cell deep sequencing libraries were prepared from oocytes/embryos (2 samples/stage) using a SOLiDTM Total RNA-seq Kit (Thermo Fisher Scientific, Waltham, MA, USA) following the manufacturer’s instructions and sequenced on a 5500xl Genetic Analyzer. The reproducibility of the preparation and sequencing methods were indicated by high Pearson correlation efficiencies between the replicates. Sequencing reads were normalized to transcripts per million as final results after trimming and mapping of the reads. We found that 8, 8, 7, 13, 10, 2, and 2 out of the 14, 52, 22, 31, 23, 4, and 3 annotated histone variants, histone methyl-tranferases, histone demethylases, histone acetyl-tranferases, histone deacetylases, DNA methyl-transferases, and DNA demethylases, respectively, were highly abundant (mean transformed transcripts per kilobase million > 50) in at least one of the pre-implantation development stages studied. Among histone variants with high mRNA abundance, H1FOO, H3F3A, and H3F3B were highly stored in oocytes, whereas other variants such as H2AFJ, H2AFV, H2AFX, H2AFY, H2AFZ, and CENPA were largely transcribed after the embryonic genome activation. H3F3A and H3F3B, however, were maintained at relatively high levels throughout pre-implantation development. Additionally, the mRNA for histone acetyl-transferases, TADA2A and TADA1; histone deacetylase, HDAC1 and HDAC3; histone methyl-transferases, EED and PRMT5; histone demethylase, KDM1A, were more abundant than others. It was also found that oocytes stored a large amount of DNA methyl-transferase, DNMT1, which degraded gradually after fertilization. Overall, in vivo-produced oocytes and early embryos contained more mRNA for histone-modifying enzymes than those for DNA modification. Taken together, our results suggest that although there are widely recognised and dramatic changes in embryonic DNA methylation through both active and passive mechanisms, the pre-implantation embryos may be more engaged in modifying histones than DNA.